Average if returns a negative value when expanding over blank selections

[ILMWT]

Hey all,

I am trying to make a formula that will average the networkday difference between the values in two different columns. Comparing Column C to Column N. Here is my formula so far...

=AVERAGE(IF(N5<>"",NETWORKDAYS('JUL 2014'!C5,'JUL 2014'!N5),""),IF(N6<>"",NETWORKDAYS('JUL 2014'!C6,'JUL 2014'!N6),""),IF(N7<>"",NETWORKDAYS('JUL 2014'!C7,'JUL 2014'!N7),0))

the first two sets of cells are populated with dates

C5 and N5
C6 and N6

So the formula works. When I expand it over C7 and N7, it returns a huge negative value. C7 is populated, N7 is not. What am I missing and how do I fix it?

Thanks all. It would be nice if I could make a formula to average the networkdays for an array, but from what I have seen I cannot do that. So this formula will end up covering all the way down to C50 most likely. It will be a long'n.


Here is what the spreadsheet looks like.
C- - - - - - - - - N
7/1/2014 7/3/2014
7/1/2014 7/9/2014
7/1/2014

 

[pgc01]

Hi

You are just adding 1 more value for the Average().

What's the value of

=IF(N7<>"",NETWORKDAYS('JUL 2014'!C7,'JUL 2014'!N7),0)

?

Also why is it that for the first 2 rows the false value for the IF() is "", but for the third row is 0?